First synthesis of α-aminophosphonates from natural porphyrin derivatives by the Kabachnik—Fields reaction

A preparative procedure is proposed for the synthesis of α-aminophosphonates of natural porphyrins by the microwave-assisted Kabachnik—Fields reaction.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 256–259, January, 2005.     

Full multinuclear resonance analysis of 4-amino-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane

The complete assignment of 19F, 1H and 13C NMR spectra for a monosubstituted octafluoro[2.2]paracyclophane derivative is described for the first time. The unambiguous assignments were achieved through the combination of 19F--1H HOESY, 1H COSY and 19F COSY techniques and then further confirmed employing a complementary approach using a Karplus-dependent 3JCF interaction. Interesting aspects of the coupling patterns for various JHH, JHF, JCF and JFF interactions are also discussed.     

Microwave-prompted Rapid and Efficient Synthesis of Diacyl Thiosemicarbazides and Semicarbazides in Solvent and Catalyst Free Condition

Eighteen 1-aroyl-4-（2-iodobenzoyl）thiosemicarbazides and corresponding semicarbazides were synthesized in excellent yield under microwave irradiation in solvent and catalyst free condition.     

微波溶样肉桂基荧光酮和表面活性剂连续荧光测定葡萄酒中铁和钴

观察到肉桂基荧光酮(略作CF)在pH≈8与Fc(Ⅲ)配位后荧光增强,CPB的加入使荧光更强,络合物与试剂荧光强度之比F_(FeR)/F_R随0～0.01μg/ml Fe(Ⅲ)线性变化,λ_(ex)=410nm,λ_(ex)=480nm;而CF在pH≈10与Co(Ⅲ)配位后荧光却减弱,乳化剂OP存在时使试剂荧光增强,若以荧光熄灭Co(Ⅲ)灵敏度便提高,试剂与络合物荧光强度之比F_R/F_(CoR)对0～0.016 μg/ml Co(Ⅲ)呈直线关系,λ_(ex)=300nm,L_(em)=352nm。控制化学条件和激发、发射波长,可不经分离测定葡萄酒(微波溶样)中铁和钴。     

5-Acyl-4-amino-2-phenyl-1,3-oxazin-6-ones

Intramolecular cyclization of acyl(ethoxycarbonyl)keteneN-benzoylaminals in boiling Ph₂O gives 5-acyl-4-amino-2-phenyl-1,3-oxazin-6-ones.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1322–1323, July, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08964).     

聚丙烯中硫酯类抗氧剂的质谱分析

采用齐格勒-钠塔催化剂使丙烯催化聚合得到聚丙烯。聚丙烯树脂本身具有优良的性能,如机械强度好,易加工成型,质量轻,成本低等,但也存在一些缺陷,如由于聚丙烯结构中存在叔碳原子,在造粒加工、贮存和使用过程中,易受热、光、氧等的作用而降解,导致材料的性能降低。为了抑制和延缓聚丙烯的氧化降解,需要在造粒阶段加入抗氧剂。本文以一种聚丙烯树脂样品为研究对象,采用溶剂抽提法提取有机添加剂,并用柱层析法对添加剂进行了分离;利用EI-MS分析了添加剂的组成,其中通过谱图解析,鉴定出添加剂中含有硫酯类抗氧剂-硫代二丙酸二(十四)酯(DMTP),并用此类常用化合物进行了验证,分析结果对树脂牌号的开发具有指导意义。     

New stationary phases of conjugated π-electron systems for HPLC—characterization of structure and dynamics by solid state NMR spectroscopy

Four new stationary phases for HPLC were prepared by modifying silica gel with a trifrnctional aminoalkyl silane. A conjugated π-electron system was linked to the amino group either directly or with a carboxylic anhydride as a spacer in between. Characterization and dynamic measurements of the new stationary phases were performed by solid state NMR spectroscopy. The results of the ²⁹si and ¹³C CP/MAS techniques were compared with the recently developed ¹H MAS-only technique. Despite strong homonuclear dipole-dipole interactions it was possible to obtain well resolved ¹H MAS spectra of those stationaru phases with a high degree of crosslinking. Limited mobility of the aromatic ligand fragments is common for all examined stationaryu phases. The chromatographic properties of the new phases were tested by their ability tio sepatate a mixture of eight PAHS. It could be shown that the π-π interaction mechanism is responsible for the separation of the eight PAHs, because the elution order of the PAHs did not changem despite the use of both a nonpolar mobile phase (n-heptane) and a polar mobile phase (methanol/ water mixture).     

Synthesis,molecular structures,and thermal decomposition of heterometallic (π-cyclooctadiene)platinum-bis(tricarbonyliron-μ3-chalcogenides)[Fe—Fe], (π-C8H12)Pt(μ3-X)2Fe2(CO)6, where X = S,Se, or Te

Transmetallation of the Fe₃(₃-X)₂(CO)₉ clusters (X = S, Se, or Te) under the action of (-C₈H₁₂)PtCl₂ afforded new heterometallic clusters (-C₈H₁₂)Pt(₃-X)₂Fe₂(CO)₆ (2—4, respectively), which were characterized by X-ray diffraction analysis. The (-C₈H₁₂)Pt fragment in these clusters is bound to two ₃-bridging chalcogen atoms X. The iron atoms are linked to each other. The coordination environment about the Pt atom is planar-square; the Pt...Fe distance is larger than 3.2 . In the synthesis of cluster 4, a new Pt complex was also obtained for which the structure (CO)₂Pt(-Te)₂Pt(CO)₂ (5) was proposed. According to the results of differential scanning calorimetry, thermal decomposition of complex 5 gave rise only to PtTe, whereas complexes 1—4 gave products with the empirical formula Fe₂PtX₂C₂O₂. The influence of the steric effects on the geometry of the clusters is discussed.     

Crystal Structure of a Supramolecular Complex Formed between 1-bromo-2-iodo-tetrafluoroethane and N,N,N′,N′-tetramethyl-ethylenediamine

X-ray analysis has revealed that N,N,N′,N′-tetramethyl-ethylenediamine 1 form donor–acceptor complex 3 with 1-bromo-2-iodo-tetrafluoroethane 2, in which the N X (X = Br, I) distances are longer than the average covalent bond length between X and N, but are also definitively shorter than the sum of the corresponding van der Waals radii of X and N, thus that indicating weak interactions between the nitrogen and bromine or iodine atoms. In our experimental section, a valuable method for recrystallization and collect X-ray data from crystals that easily exhibit decay and can be cracked is reported.     

Poly[3-(3,4-dihydroxyphenyl)glyceric acid] from Stems of <Emphasis Type="Italic">Symphytum asperum</Emphasis> and <Emphasis Type="Italic">S. caucasicum</Emphasis>

Two high-molecular-weight (>1000 kDa) water-soluble preparations were isolated from stems of Symphytum asperum and S. caucasicum. Their basic component was established as poly[hydroxy-1-carboxy-2-(3,4-dihydroxyphenyl)ethylene], analogous to that of high-molecular-weight (>1000 kDa) preparations from roots of these same plants, using IR and NMR spectral data. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 303–305, July–August, 2005. An erratum to this article is available at .